Hello,
We ran automated tests on a recent commit from this kernel tree:
Kernel repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
Commit: c7cfa74dd315 - Linux 5.4.6-rc1
The results of these automated tests are provided below.
Overall result: PASSED
Merge: OK
Compile: OK
Tests: OK
All kernel binaries, config files, and logs are available for download here:
https://artifacts.cki-project.org/pipelines/349420
Please reply to this email if you have any questions about the tests that we
ran or if you have any suggestions on how to make future tests more effective.
,-. ,-.
( C ) ( K ) Continuous
`-',-.`-' Kernel
( I ) Integration
`-'
______________________________________________________________________________
Compile testing
---------------
We compiled the kernel for 3 architectures:
aarch64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
ppc64le:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
x86_64:
make options: -j30 INSTALL_MOD_STRIP=1 targz-pkg
Hardware testing
----------------
We booted each kernel and ran the following tests:
aarch64:
Host 1:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP
✅ Loopdev Sanity
✅ Memory function: memfd_create
✅ AMTU (Abstract Machine Test Utility)
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ httpd: mod_ssl smoke sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ storage: SCSI VPD
✅ stress: stress-ng
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ jvm test suite
🚧 ✅ Memory function: kaslr
🚧 ✅ LTP: openposix test suite
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ audit: audit testsuite test
🚧 ✅ iotop: sanity
🚧 ✅ Usex - version 1.9-29
🚧 ✅ storage: dm/common
Host 2:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
ppc64le:
Host 1:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ IPMI driver test
🚧 ✅ IPMItool loop stress test
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Host 2:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP
✅ Loopdev Sanity
✅ Memory function: memfd_create
✅ AMTU (Abstract Machine Test Utility)
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns tunnel
✅ httpd: mod_ssl smoke sanity
✅ tuned: tune-processes-through-perf
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ jvm test suite
🚧 ✅ Memory function: kaslr
🚧 ✅ LTP: openposix test suite
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ audit: audit testsuite test
🚧 ✅ iotop: sanity
🚧 ✅ Usex - version 1.9-29
🚧 ✅ storage: dm/common
x86_64:
Host 1:
✅ Boot test
✅ Storage SAN device stress - megaraid_sas
Host 2:
✅ Boot test
✅ Storage SAN device stress - mpt3sas driver
Host 3:
⚡ Internal infrastructure issues prevented one or more tests (marked
with ⚡⚡⚡) from running on this architecture.
This is not the fault of the kernel that was tested.
⚡⚡⚡ Boot test
⚡⚡⚡ xfstests: ext4
⚡⚡⚡ xfstests: xfs
⚡⚡⚡ lvm thinp sanity
⚡⚡⚡ storage: software RAID testing
🚧 ⚡⚡⚡ IOMMU boot test
🚧 ⚡⚡⚡ IPMI driver test
🚧 ⚡⚡⚡ IPMItool loop stress test
🚧 ⚡⚡⚡ selinux-policy: serge-testsuite
🚧 ⚡⚡⚡ power-management: cpupower/sanity test
🚧 ⚡⚡⚡ Storage blktests
Host 4:
✅ Boot test
✅ Podman system integration test (as root)
✅ Podman system integration test (as user)
✅ LTP
✅ Loopdev Sanity
✅ Memory function: memfd_create
✅ AMTU (Abstract Machine Test Utility)
✅ Networking bridge: sanity
✅ Ethernet drivers sanity
✅ Networking MACsec: sanity
✅ Networking socket: fuzz
✅ Networking sctp-auth: sockopts test
✅ Networking: igmp conformance test
✅ Networking route: pmtu
✅ Networking route_func: local
✅ Networking route_func: forward
✅ Networking TCP: keepalive test
✅ Networking UDP: socket
✅ Networking tunnel: geneve basic test
✅ Networking tunnel: gre basic
✅ L2TP basic test
✅ Networking tunnel: vxlan basic
✅ Networking ipsec: basic netns transport
✅ Networking ipsec: basic netns tunnel
✅ httpd: mod_ssl smoke sanity
✅ tuned: tune-processes-through-perf
✅ pciutils: sanity smoke test
✅ ALSA PCM loopback test
✅ ALSA Control (mixer) Userspace Element test
✅ storage: SCSI VPD
✅ stress: stress-ng
✅ trace: ftrace/tracer
🚧 ✅ CIFS Connectathon
🚧 ✅ POSIX pjd-fstest suites
🚧 ✅ jvm test suite
🚧 ✅ Memory function: kaslr
🚧 ✅ LTP: openposix test suite
🚧 ✅ Networking vnic: ipvlan/basic
🚧 ✅ audit: audit testsuite test
🚧 ✅ iotop: sanity
🚧 ✅ Usex - version 1.9-29
🚧 ✅ storage: dm/common
Host 5:
✅ Boot test
✅ xfstests: ext4
✅ xfstests: xfs
✅ lvm thinp sanity
✅ storage: software RAID testing
🚧 ✅ IOMMU boot test
🚧 ✅ IPMI driver test
🚧 ✅ IPMItool loop stress test
🚧 ✅ selinux-policy: serge-testsuite
🚧 ✅ Storage blktests
Test sources: https://github.com/CKI-project/tests-beaker
💚 Pull requests are welcome for new tests or improvements to existing tests!
Waived tests
------------
If the test run included waived tests, they are marked with 🚧. Such tests are
executed but their results are not taken into account. Tests are waived when
their results are not reliable enough, e.g. when they're just introduced or are
being fixed.
Testing timeout
---------------
We aim to provide a report within reasonable timeframe. Tests that haven't
finished running are marked with ⏱. Reports for non-upstream kernels have
a Beaker recipe linked to next to each host.
Currently slab percpu vmstats are flushed twice: during the memcg
offlining and just before freeing the memcg structure.
Each time percpu counters are summed, added to the atomic counterparts
and propagated up by the cgroup tree.
The problem is that percpu counters are not zeroed after the first
flushing. So every cached percpu value is summed twice. It creates
a small error (up to 32 pages per cpu, but usually less) which
accumulates on parent cgroup level. After creating and destroying
of thousands of child cgroups, slab counter on parent level can
be way off the real value.
For now, let's just stop flushing slab counters on memcg offlining.
It can't be done correctly without scheduling a work on each cpu:
reading and zeroing it during css offlining can race with an
asynchronous update, which doesn't expect values to be changed
underneath.
With this change, slab counters on parent level will become eventually
consistent. Once all dying children are gone, values are correct.
And if not, the error is capped by 32 * NR_CPUS pages per dying
cgroup.
It's not perfect, as slab are reparented, so any updates after
the reparenting will happen on the parent level. It means that
if a slab page was allocated, a counter on child level was bumped,
then the page was reparented and freed, the annihilation of positive
and negative counter values will not happen until the child cgroup is
released. It makes slab counters different from others, and it might
want us to implement flushing in a correct form again.
But it's also a question of performance: scheduling a work on each
cpu isn't free, and it's an open question if the benefit of having
more accurate counters is worth it.
We might also consider flushing all counters on offlining, not only
slab counters.
So let's fix the main problem now: make the slab counters eventually
consistent, so at least the error won't grow with uptime (or more
precisely the number of created and destroyed cgroups). And think
about the accuracy of counters separately.
Signed-off-by: Roman Gushchin <guro(a)fb.com>
Fixes: bee07b33db78 ("mm: memcontrol: flush percpu slab vmstats on kmem offlining")
Cc: stable(a)vger.kernel.org
---
include/linux/mmzone.h | 5 ++---
mm/memcontrol.c | 37 +++++++++----------------------------
2 files changed, 11 insertions(+), 31 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 89d8ff06c9ce..5334ad8fc7bd 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -215,9 +215,8 @@ enum node_stat_item {
NR_INACTIVE_FILE, /* " " " " " */
NR_ACTIVE_FILE, /* " " " " " */
NR_UNEVICTABLE, /* " " " " " */
- NR_SLAB_RECLAIMABLE, /* Please do not reorder this item */
- NR_SLAB_UNRECLAIMABLE, /* and this one without looking at
- * memcg_flush_percpu_vmstats() first. */
+ NR_SLAB_RECLAIMABLE,
+ NR_SLAB_UNRECLAIMABLE,
NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
WORKINGSET_NODES,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 601405b207fb..3165db39827a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3287,49 +3287,34 @@ static u64 mem_cgroup_read_u64(struct cgroup_subsys_state *css,
}
}
-static void memcg_flush_percpu_vmstats(struct mem_cgroup *memcg, bool slab_only)
+static void memcg_flush_percpu_vmstats(struct mem_cgroup *memcg)
{
- unsigned long stat[MEMCG_NR_STAT];
+ unsigned long stat[MEMCG_NR_STAT] = {0};
struct mem_cgroup *mi;
int node, cpu, i;
- int min_idx, max_idx;
-
- if (slab_only) {
- min_idx = NR_SLAB_RECLAIMABLE;
- max_idx = NR_SLAB_UNRECLAIMABLE;
- } else {
- min_idx = 0;
- max_idx = MEMCG_NR_STAT;
- }
-
- for (i = min_idx; i < max_idx; i++)
- stat[i] = 0;
for_each_online_cpu(cpu)
- for (i = min_idx; i < max_idx; i++)
+ for (i = 0; i < MEMCG_NR_STAT; i++)
stat[i] += per_cpu(memcg->vmstats_percpu->stat[i], cpu);
for (mi = memcg; mi; mi = parent_mem_cgroup(mi))
- for (i = min_idx; i < max_idx; i++)
+ for (i = 0; i < MEMCG_NR_STAT; i++)
atomic_long_add(stat[i], &mi->vmstats[i]);
- if (!slab_only)
- max_idx = NR_VM_NODE_STAT_ITEMS;
-
for_each_node(node) {
struct mem_cgroup_per_node *pn = memcg->nodeinfo[node];
struct mem_cgroup_per_node *pi;
- for (i = min_idx; i < max_idx; i++)
+ for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
stat[i] = 0;
for_each_online_cpu(cpu)
- for (i = min_idx; i < max_idx; i++)
+ for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
stat[i] += per_cpu(
pn->lruvec_stat_cpu->count[i], cpu);
for (pi = pn; pi; pi = parent_nodeinfo(pi, node))
- for (i = min_idx; i < max_idx; i++)
+ for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
atomic_long_add(stat[i], &pi->lruvec_stat[i]);
}
}
@@ -3403,13 +3388,9 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg)
parent = root_mem_cgroup;
/*
- * Deactivate and reparent kmem_caches. Then flush percpu
- * slab statistics to have precise values at the parent and
- * all ancestor levels. It's required to keep slab stats
- * accurate after the reparenting of kmem_caches.
+ * Deactivate and reparent kmem_caches.
*/
memcg_deactivate_kmem_caches(memcg, parent);
- memcg_flush_percpu_vmstats(memcg, true);
kmemcg_id = memcg->kmemcg_id;
BUG_ON(kmemcg_id < 0);
@@ -4913,7 +4894,7 @@ static void mem_cgroup_free(struct mem_cgroup *memcg)
* Flush percpu vmstats and vmevents to guarantee the value correctness
* on parent's and all ancestor levels.
*/
- memcg_flush_percpu_vmstats(memcg, false);
+ memcg_flush_percpu_vmstats(memcg);
memcg_flush_percpu_vmevents(memcg);
__mem_cgroup_free(memcg);
}
--
2.17.1